COLD ADAPTATION PARAMETERS DERIVED FROM CDNA SEQUENCING AND MOLECULARMODELING OF ELASTASE FROM ANTARCTIC FISH NOTOTHENIA-NEGLECTA

The primary structure of an elastase from the Antarctic fish Nototheni a neglecta (NE) was elucidated by molecular cloning and cDNA sequence analysis. The cDNA of interest was isolated from a cDNA library obtain ed from Notothenia's pyloric caeca. The amino acid sequence identity w ith mammalian elastases ranges between 53 and 64%, but interestingly r eaches 79% with one isoform (CEB) of two recently isolated cod elastas es. The most interesting changes distinguishing the model of NE, predi cted from the three dimentional structure of the native porcine elasta se (PE), concern the catalytic crevice located in the inter-domains re gion. These features might be involved in the adaptation to cold of th e Antarctic elastase.